The use of two-stage airbags may be conventional, and even continuously switchable airbags may be possible.
A device having an airbag controller and external acceleration sensors is described in German Published Patent Application No. 199 45 614. A device having an acceleration sensor for impact detection, having a processor, a memory and at least one airbag that may be switched in two stages, is described in German Published Patent Application No. 199 63 267. German Published Patent Application No. 197 43 009 describes a side impact airbag that may deploy if one of the measured values of one of the metrics, lateral velocity or lateral acceleration, is above the corresponding discrimination threshold at the time, or the other measured value or the other metric (lateral acceleration or side airbag) is above the corresponding safeguard threshold. From German Published Patent Application No. 199 09 538 a method of controlling the triggering of a motor vehicle occupant protection system is described in which an acceleration signal may be used to calculate a criterion that is compared to a dynamic threshold value. In this case there may be different dynamic threshold values for the first and the second stages.